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Field evidences showing rapid frontal degeneration of the Kangriz glacier,western Himalayas,Jammu&Kashmir

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Journal of Mountain Science 2018年第6期15卷 1199-1208页

作者： GARG Siddhi shukla Aparna MEHTA Manish KUMAR Vinit SAMUEL Shruti Anna BARTARYA S.K. shukla Uma kant Wadia Institute o/Himalayan Geology 33 GMS Road Dehradun 248001 India Department of Geology Banaras Hindu University Varanasi 221005 India

Life cycle of glaciers in the Himalayan region has notably changed due to the climatic variability since last few decades. Glaciers across the world and specially the Himalayan glaciers have shown large scale degeneration in the last few decades. Himalayan glaciers serve as an important fresh water resource for the downstream communities, who are dependent on this water for domestic and other purposes. Therefore, glacier shrinkage and the associated hydrological changes pose a significant problem for regional-scale water budgets and resource management. These issues necessitate the regular and rigorous monitoring of the wastage pattern of the Himalayan glaciers in field and using satellite remote sensing data. In this work, we report rapid and enhanced degeneration of the frontal part of the Kangriz glacier, Jammu and Kashmir(J & K), in terms of surface melting, debris cover, snout characteristics and meltwater discharge. Ablation data acquired during 2016-2017 shows the average lowering of the frontal part of the glacier to be ~148 ± 34 cm, one-third of which was found to have occurred within a 13 day time period in September, 2017. Also, the quantum of ice melt was found to be inversely influenced(r =-0.84) by the debris thickness. 15 day meltwater discharge measurement revealed its strong relationship with snout disintegration pattern, evidenced twice during the said time period. Volume of water discharged from the glacier was estimated to be 7.91×10~6 m^3 for the measurement duration. Also, mean daily discharge estimated for the 15 days interval showed good positive correction(r = 0.78) with temperature indicating the direct dependency of the former on land surface temperature conditions of the region. Besides the lowering and discharge observations, the frequent ice-block break-offs at the glacier snout further enhance its overall drastic degeneration. The study suggests that, being the largest glacier in the Suru basin, the Kangriz glacier needs to be continuo

关键词： Glacier shrinkage Western Himalayas Surface lowering Degeneration Meltwater discharge

Effect of local longitudinal shortening on the transport of luminal contents through small intestine

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Acta Mechanica Sinica 2019年第1期35卷 45-60,I0002页

作者： Ravi kant Avvari Sasi Institute of Technology and Engineering Tadepalligudem 534101India

A theoretical analysis of the rheological fluid flow due to peristalsis is studied. We have applied the classical lubrication theory to predict the near physiological behavior of the intestinal segment, mixing and transport. A parametric study involving the changes in local longitudinal shortening (LLS) magnitude, LLS spacing, fluid viscosity, wavelength of the wave, and occlusion of lumen caused by the wave provided insights into the dynamics of the peristalsis flow of a non-Newtonian fluid. LLS appear to have little significance in modulating the flow patterns that are caused by circular contraction alone. Results also indicate that there exists trade-off between the power requirement for peristalsis at a certain occlusion against the percentage LLS. LLS appear to be more advantageous to perform the peristalsis activity at higher occlusion than lower occlusion. Having mucosal folds in the inner lining of the intestine allows for one more advantage of slowing the transit due to increased friction factor and increase in time for absorption of the nutrients.

关键词： Circular contraction Local longitudinal shortening Lubrication theory

Latitudinal fluctuation in global concentration of CO2 and CH4 from shortwave infrared spectral observation by GOSAT during COVID-19

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International Journal of Digital Earth 2021年第12期14卷 1882-1896页

作者： Laxmi kant Sharma Rajani kant Verma Department of Environmental Science School of Earth SciencesCentral University of RajasthanAjmerIndia

Various countries have rapidly implemented strict actions to slow the blowout of *** events were dis-regarded,and anthropogenic activities such as industrial and transport systems were at a *** countries were on lockdown,including the largest emitters of carbon *** to these lockdowns,anthropogenic activities have been reduced and reported that air quality improves at a regional scale in many countries,including ***,the current study using Greenhouse Gases Observing Satellite(GOSAT/IBUKI)datasets to monitor the fluctuation of the average global concentration of dry mole fractions of atmospheric Methane(CH_(4))and Carbon Dioxide(CO_(2))during these pandemic lockdowns from January to June *** emphasize no significant reduction in the average concentration of dry mole fractions of atmospheric CH_(4) over the globe,but a minor reduction was observed in global CO_(2) *** average concentration of both gases compares at each ten-degree *** study reveals that,against the regional breakdowns,these short time lockdowns are not enough to control the concentration of these greenhouse gases at a larger scale,such as 10°latitude and globally,except for a minor reduction in CO_(2) concentration.

关键词： Lockdown pandemic air quality greenhouse gas methane carbon dioxide

Cosmological parameters for spatially flat dust filled Universe in Brans-Dicke theory

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Research in Astronomy and Astrophysics 2017年第3期17卷 55-66页

作者： Gopi kant Goswami Department of Mathematics Kalyan E G.CollegeBhilai-490 006C.G.India

We have investigated late time acceleration for a spatially fiat dust filled Universe in Brans- Dicke theory in the presence of a positive cosmological constant A. Expressions for Hubble＇s constant, luminosity distance and apparent magnitude have been obtained for our model. The theoretical results are compared with observed values of the latest 287 high redshift （0.3 ≤ z ≤1.4） Type Ia supernova data taken from the Union 2.1 compilation to estimate present values of matter and dark energy parame- ters, （Ωm）0 and （ΩA）0. We have also estimated the present value of Hubble＇s constant H0 in light of an updated sample of Hubble parameter measurements including 19 independent data points. The results are found to be in good agreement with recent astrophysical observations. We also calculated various physical parameters such as matter and dark energy densities, present age of the Universe and decelera- tion parameter. The value for Brans-Dicke-coupling constant ω is set to be 40 000 based on accuracy of solar system tests and recent experimental evidence.

关键词： cosmology osmological parameters - cosmology observations- dark energy-Brans-Dicke theory

Bird assemblages in natural and urbanized habitats along elevational gradient in Nainital district （western Himalaya） of Uttarakhand state, India

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Current Zoology 2011年第3期57卷 318-329页

作者： Dinesh BHATT Kamal kant JOSHI Avian Diversity and Bioacoustics Lab Department of Zoology and Environmental Science Gurukula Kangri University Harid- war 249 404 Uttarakhand India

The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amongst habitat types remains unclear in India. We attempted to estimate bird assemblages in terms of diversity, species composition, status and abun- dance in urban and forest habitats of Nainital district of Uttarakhand （350-2450 m asl; 29N）, Western Himalayas. We sampled different elevational gradients and to understand the effect of urbanization and season on avian community composition. Field studies were conducted during January 2005 to January 2007. Results indicated that the forest had more complex bird community structure in terms of higher species richness （14.35 vs 8.69）, higher species diversity （Shannon＇s index 4.00 vs 3.54）, higher evenness （0.838 vs 0.811） and more rare species （17 vs 5） as compared to urban habitat. However, the abundance of 11 species was higher in urban habitats. Bird Species Richness （BSR） varied considerably among study areas （91 to 113 species）, was high- est （113 species） at mid elevation （1450-1700 m asl） and decreased （22 species） at high elevation （1900-2450 m asl）. It seems that high BSR at mid altitudes is not caused by the presence of a group of mid altitude specialists but rather that there is an over- lap in the distribution of low land and high elevation specialists at this altitude. BSR and Bird Species Diversity fluctuated across seasons but not habitat type [Current Zoology 57 （3）： 318-329,2011].

关键词： Avian biodiversity Western Himalaya Urbanization

Reconstructing Missing Hourly Real-Time Precipitation Data Using a Novel Intermittent Sliding Window Period Technique for Automatic Weather Station Data

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Journal of Meteorological Research 2017年第4期31卷 774-790页

作者： Nagaraja HEMA Krishna kant Department of Computer Science and Engineering/Information Technology Jaypee Institute of Information Technology Noida 201307 India

Precipitation is the most discontinuous atmospheric parameter because of its temporal and spatial variability. Precipitation observations at automatic weather stations（AWSs） show different patterns over different time periods. This paper aims to reconstruct missing data by finding the time periods when precipitation patterns are similar, with a method called the intermittent sliding window period（ISWP） technique—a novel approach to reconstructing the majority of non-continuous missing real-time precipitation data. The ISWP technique is applied to a 1-yr precipitation dataset（January 2015 to January 2016）, with a temporal resolution of 1 h, collected at 11 AWSs run by the Indian Meteorological Department in the capital region of Delhi. The acquired dataset has missing precipitation data amounting to 13.66%, of which 90.6% are reconstructed successfully. Furthermore, some traditional estimation algorithms are applied to the reconstructed dataset to estimate the remaining missing values on an hourly basis. The results show that the interpolation of the reconstructed dataset using the ISWP technique exhibits high quality compared with interpolation of the raw dataset. By adopting the ISWP technique, the root-mean-square errors（RMSEs）in the estimation of missing rainfall data—based on the arithmetic mean, multiple linear regression, linear regression,and moving average methods—are reduced by 4.2%, 55.47%, 19.44%, and 9.64%, respectively. However, adopting the ISWP technique with the inverse distance weighted method increases the RMSE by 0.07%, due to the fact that the reconstructed data add a more diverse relation to its neighboring AWSs.

关键词： automatic weather station intermittent sliding window period interpolation mean absolute error reconstruction of missing precipitation data

Effect of pulse slippage on density transition-based resonant third-harmonic generation of short-pulse laser in plasma

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Frontiers of physics 2016年第4期11卷 163-170页

作者： Vishal Thakur Niti kant Department of Physics Lovely Professional University Phagwara-144411 Punjab India

The resonant third-harmonic generation of a tion was investigated. Because of self-focusing self-focusing laser in plasma with a density transi- of the fundamental laser pulse, a transverse intensity gradient was created, which generated a plasma wave at the fundamental wave frequency. Phase matching was satisfied by using a Wiggler magnetic field, which provided additional angular too- mentum to the third-harmonic photon to make the process resonant. An enhancement was observed in the resonant third-harmonic generation of an intense short-pulse laser in plasma embedded with a magnetic Wiggler with a density transition. A plasma density ramp played an important role in the self-focusing, enhancing the third-harmonic generation in plasma. We also examined the ef- fect of the Wiggler magnetic field on the pulse slippage of the third-harmonic pulse in plasma. The pulse slippage was due to the group-velocity mismatch between the fundamental and third-harmonic pulses.

关键词： short pulse laser pulse slippage third harmonic generation plasma

Characterization and modification of waste magnesium chip utilized as an Mg-rich intermetallic composite

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Particuology 2014年第6期12卷 158-164页

作者： Aysel kantürk Figen Sabriye Piskin Department of Chemical Engineering Yildiz Technical University

In this study,the characterization and modification of waste magnesium chips（WMCs）,which were produced by plastic molding in a gold manufacturing factory and are used as Mg-rich intermetallic composites in storing hydrogen,were discussed in *** were analyzed using X-ray diffraction（XRD）,X-ray fluorescence（XRF） spectroscopy,differential scanning calorimetry（DSC）,scanning electron microscopy（SEM）,and Brunauer-Emmett-Teller（BET） analysis to characterize the materials’ structural *** milling,organic treatment,and inorganic salt addition were carried out to modify the WMCs’ surface to prepare Mg-rich intermetallic composites for storing *** modified samples were analyzed using high-pressure volumetric analyses to calculate their hydrogen storage *** authors conclude that modified WMC was promising as an Mg-rich intermetallic composite that was suitable for use in hydrogen storage with a 4.59 wt%capacity at 320 C under a hydrogen pressure of 60 bar.

关键词： Waste magnesium chip Characterization Modification Hydrogen storage Intermetallic composite

Multivariable regression model for Fox depth correction factor

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Frontiers of Structural and Civil Engineering 2019年第1期13卷 103-109页

作者： Ravi kant MITTAL Sanket RAWAT Piyush BANSAL Department of Civil Engineering Birla Institute of Technology & SciencePilani 333031India Department of Civil and Environmental Engineering Virginia TechBlacksburgVA 24061USA

This paper presents a simple and efficient equation for calculating the Fox depth correction factor used in computation of settlement reduction due to foundation *** solution of Boussinesq theory was used originally to develop the Fox depth correction factor equations which were rather complex in *** equations were later simplified in the form of graphs and tables and referred in various international code of practices and standard texts for an unsophisticated and quick ***,these tables and graphs provide the factor only for limited values of the input variables and hence again complicates the process of automation of ***,this paper presents a non-linear regression model for the analysis of effect of embedment developed using "IBM Statistical Package for the Social Sciences" *** multiple iterations,the value of coefficient of determination is found to reach *** equation is straightforward,competent and easy to use for both manual and automated calculation of the Fox depth correction factor for wide range of input *** the developed equation,parametric study is also conducted in the later part of the paper to analyse the extent of effect of a particular variable on the Fox depth factor.

关键词： settlement embedment Fox depth correction factor regression multivariable